About the Role
What if your C# expertise could directly shape the infrastructure powering the next generation of AI? We're looking for a Senior Backend Engineer to design and build the high-performance data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on to train and improve their models.
This is a fully remote contract role with meaningful technical scope. You'll work on real production systems — not toy projects — alongside data, research, and engineering teams at the frontier of AI development.
- Organization: Alignerr
- Type: Hourly Contract
- Location: Remote
- Commitment: 20–40 hours/week
What You'll Do
- Design, build, and optimize high-performance backend systems in C# supporting AI data pipelines and evaluation workflows
- Develop backend services and tooling for large-scale data annotation, validation, and quality control
- Build and maintain RESTful APIs and RPC services for reliable inter-service communication
- Integrate with cloud-native data services and orchestrate workflows via message bus architectures
- Improve reliability, performance, and safety across existing C# codebases
- Identify bottlenecks and edge cases in data and system behavior, then implement scalable, durable fixes
- Collaborate with data, research, and engineering teams to support model training and evaluation workflows
- Participate in synchronous design reviews to iterate on architecture and implementation decisions
Who You Are
- 5+ years of professional experience building scalable backend services in C#
- Strong systems programming background with full-stack exposure
- Mastery of modern frameworks for building RESTful APIs and RPC services
- Experienced with cloud-native data services and message bus / event-driven architectures
- Native or fluent English speaker with clear written and verbal communication skills
- Self-directed and reliable — able to commit 20–40 hours per week and deliver consistently
- Sharp eye for performance bottlenecks, edge cases, and system-level failure modes
Nice to Have
- Prior experience with data annotation, data quality pipelines, or model evaluation systems
- Familiarity with AI/ML workflows, model training, or benchmarking infrastructure
- Experience with distributed systems, developer tooling, or data orchestration platforms
Why Join Us
- Work on cutting-edge AI infrastructure projects alongside leading research labs
- Fully remote and flexible — work from anywhere, on a schedule that suits you
- Freelance autonomy with the structure and purpose of high-impact engineering work
- Make a direct, tangible contribution to the systems that shape how AI models are built and evaluated
- Potential for ongoing work and contract extension as new projects launch